US Federal law enforcement officials have named the parcel-bomb suspect as Cesar Sayoc.
Authorities arrested a man in Florida on Friday after a wave of pipe explosive devices were sent to prominent Democrats and critics of Donald Trump.
The man was taken into custody in a car park of a shop in Plantation, near Fort Lauderdale.
A van, reportedly plastered in right-wing stickers, was removed on a truck.
Sayoc was born in 1962, and more arrests could follow, a federal law enforcement official told Reuters.
The manager of a used-car shop next to the AutoZone car park said: “I heard like a bomb.
Two more suspicious packages were addressed to US Senator Cory Booker and ex-US director of national intelligence, James Clapper on Friday.